Geopix UK - Glaciation

Glacial Areas

Each glacier is different, even though the broad characteristics may be the same for each example. Some of these differences include

the size
the rate of flow
the source of the ice
polar or temperate situation
mountain or lowland situation
whether or not the snout reaches the sea
whether or not the snout is retreating

Each glacier has its own setting within the scenery of the area, and is worth investigating in its own right.

Modern glaciers give an insight into the scenery of the British Isles, much of which has been influenced in one way or another by glaciation during the last Ice Age.

Mount McKinley, Alaska

Mt McKinley or Denali ("the great one"),
in Denali National Park, is North America's highest peak.
Its altitude (6194m), latitude (63N) and position on the edge of the continent all encourage the high snowfall which feeds the glaciers that spread out from the central ridge.

College Fjord, Alaska

A number of tide-water glaciers flow down into College Fjord, a wide and accessible seaway which makes for easy sight-seeing. The glaciers are named after colleges and universities on the east coast of America.
This area was the centre of the magnitude 8.6 Alaskan earthquake of 1964. The Fjord lies inside Prince William Sound, the terminus for the trans-Alaskan oil pipe-line.

Mendenhall Glacier, Alaska

Mendenhall Glacier, near the state capital of Juneau,
is one of the most southerly of the Alaskan glaciers, the first one you come to sailing north from Vancouver.
As with many glaciers today, it is retreating, at an average of 10m a year. The lake at the snout of the glacier was formed in 1910, during the retreat. In this case, however, modern global warming is not entirely to blame - the snout has retreated by 4000m in the last 200 years.

South Shetland Islands, Antarctica

These islands lie off the coast of the Antarctic Peninsula. Despite their relatively small size, each one maintains its own glacier(s). Precipitation is high and the temperatures low, favouring the accumulation of snow.

The Beagle Channel, Tierra del Fuego, South America

The Beagle Channel, named after the ship in which Darwin visited South America on his famous voyage, shows all the hallmarks of a (flooded) glaciated valley.

It is a good revision exercise to try to explain how we know that the Channel was formed by glacial erosion (and modified by glacial deposition).
One clue is the presence of glaciers in the tributary valleys, some of which reach sea level, and some of which do not.
Are they retreating as well? The signs are there.

Owenmore Valley, Dingle, Ireland

Not glaciated at the moment, but it was - about 12,000 years ago.

How do we know?
From the evidence left behind when the Pleistocene
ice-sheets melted.
Again, it is good revision exercise to try to explain the present landforms in terms of past erosion and deposition.
Can you certain that erosion was caused by ice? Why?
Could it be caused by rivers? Why not?